The present disclosure relates to a gas turbine engine and, more particularly, to a geared architecture therefor.
Epicyclic gear systems with planetary or star gearboxes may be used in gas turbine engines for their compact designs and efficient high gear reduction capabilities. Planetary and star gearboxes generally include three gear train elements: a central sun gear, an outer ring gear with internal gear teeth, and a plurality of planet gears supported by a planet carrier between and in meshed engagement with both the sun gear and the ring gear. The gear train elements share a common longitudinal central axis, about which at least two rotate.
In some gas turbine engine architectures where speed reduction transmission is required, the central sun gear generally receives rotary input from the engine core, the outer ring gear is stationary and the planet gear carrier rotates in the same direction as the sun gear to provide torque output at a reduced rotational speed. In contrast, in star gear trains, the planet carrier is held stationary and the output shaft is driven by the ring gear in a direction opposite that of the sun gear.
The epicyclic gear systems require lubrication during operation and typically include oil spray bar and oil baffles within the carriers. Although effective, such carrier arrangements typically require multiple components and relatively complicated assembly in which side walls of the carrier are assembled around the planet gears, separate oil spray bars and oil baffles.